Influence of Oxidation on Coating Formation in Thermal Spraying

Plasma spray processes have been widely used to produce high performance coatings of a wide range of Materials (metallic, non-metallic, ceramics), offering protection from, eg. wear, extreme temperature, chemical attack and environmental corrosion. To obtain good quality coatings, spray parameters must be carefully selected. Due to the large variety in process parameters, it is difficult to optimize the process for each specific coating and substrate combinations. Furthermore modelling the spray process allows a better understanding of the process sequences during thermal spraying. Good agreement of the virtual spraying process with the real coating formation is achieved by modelling the particular process steps. The simulation of coating formation to estimate the process parameters is an important tool to develop new coating structures with defined properties. In this work, the process of plasma sprayed coating has been analyzed by numerical simulation. Commercial code is used to predict the plasma jet characteristics, plasma –particle interaction, and coating formation. Using this model we can obtain coating microstructure and characteristics which form a foundation for further improvement of an advanced ceramic coating build up model.

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Hybrid Plasma Spraying —Discovering the Effects of Deposition Parameters

10.31399/asm.cp.itsc2021p0493 ◽

2021 ◽

Author(s):

Tomas Tesar ◽

Radek Musalek ◽

Jan Medricky ◽

Jan Cizek ◽

Frantisek Lukac ◽

...

Keyword(s):

Plasma Spraying ◽

Thermal Spraying ◽

Hybrid Coatings ◽

Deposition Parameters ◽

Wide Range ◽

Hybrid Plasma ◽

Coating Formation ◽

Liquid Feedstock ◽

Multiple Case ◽

Sprayed Coatings

Abstract Hybrid plasma spraying is emerging as the next potential technology leap in thermal spraying. The combination of high throughput and deposition rates of coatings sprayed from powders with the tailored functionality of liquid-feedstock sprayed coatings appears highly promising for a wide range of applications. Moreover, possible refined mixtures of different materials come readily with the utilization of multiple feedstocks with varying particle sizes. However, the practical aspects of hybrid coatings production are accompanied with several peculiarities not encountered when using distinct feedstocks. To deepen the understanding of this novel route, this paper presents fundamental hybrid coating formation principles and the effect of selected deposition parameters using multiple case-study material systems, such as Al2O3-YSZ, Al2O3-Cr2O3, and Al2O3-TiO2.

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Present Status and Future Prospects of Cold Spraying

Materials Science Forum ◽

10.4028/www.scientific.net/msf.534-536.433 ◽

2007 ◽

Vol 534-536 ◽

pp. 433-436 ◽

Cited By ~ 6

Author(s):

Frank Gaertner ◽

Tobias Schmidt ◽

Heinrich Kreye

Keyword(s):

New Technology ◽

Thermal Spraying ◽

Cold Spraying ◽

Spray Forming ◽

Full Potential ◽

Spray Parameters ◽

Present Contribution ◽

High Kinetic Energy ◽

Coating Formation ◽

New Applications

Cold spraying is a fairly new coating technique, which within the last decade attracted serious attention of research groups and spray companies. As compared to thermal spraying, the low process temperatures in cold spraying result in unique coating properties, which promise new applications. Since particles impact with high kinetic energy in the solid state, new concepts to describe coating formation are requested to enable the full potential of this new technology. The present contribution gives a brief review of current models concerning bonding, supplying a description of the most influential spray parameters and consequences for new developments. With respect to spray forming by cold cold spraying, microstructures and thick, further machineable structures are presented.

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Mathematical Model for Process Thermal Spraying Coating Formation

Thermal Spray 1996: Proceedings from the National Thermal Spray Conference ◽

10.31399/asm.cp.itsc1996p0569 ◽

1996 ◽

Author(s):

A. Ilyuchenko ◽

P. Vityaz ◽

V. Okovity ◽

V. Abrashin ◽

G. Gromyko ◽

...

Keyword(s):

Mathematical Model ◽

Bond Strength ◽

Stokes Equations ◽

Numerical Technique ◽

Thermal Spraying ◽

Spray Coating ◽

Navier Stokes ◽

Navier Stokes Equations ◽

Coating Formation ◽

Particle Spreading

Abstract This paper presents a mathematical model of the plasma-spray coating formation process that allows one to estimate bond strength energy, a parameter related to coating quality. Bond strength energy is defined on the basis of particle-substrate or system balance. Unknown quantities in the energy equation are obtained from nonstationary Navier-Stokes equations for velocity field and pressure and from thermoelasticity equations for temperature and stress. Complexities associated with particle spreading and nonlinear hydrodynamics have made it necessary to develop a stable numerical technique.

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Mathematical Modeling of High Velocity Oxygen Fuel Thermal Spraying: An Overview

10.1115/imece2000-2689 ◽

2000 ◽

Author(s):

D. Cheng ◽

G. Trapaga ◽

J. W. McKelliget ◽

E. J. Lavernia

Keyword(s):

High Velocity ◽

Thermal Spraying ◽

High Velocity Oxygen Fuel ◽

Combustion Gas ◽

Hvof Thermal Spray ◽

Hvof Thermal Spraying ◽

Coating Formation ◽

Versatile Technique ◽

Thermal Spray Processes ◽

Oxygen Fuel

Abstract High velocity oxygen fuel (HVOF) thermal spraying is a versatile technique widely used for the manufacture of coatings from various materials system. The physical, mechanical, and chemical characteristics of a coating are critically influenced by the operating parameters used to obtain maximum coating performance while minimizing experimentation. In this paper, modeling of HVOF thermal spray processes is reviewed, paying particular attention to combustion, gas/particle dynamics, particle impingement, and coating formation.

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